Comparing Categorical and Probabilistic Fingerprint Evidence

Fingerprint examiners traditionally express conclusions in categorical terms, opining that impressions do or do not originate from the same source. Recently, probabilistic conclusions have been proposed, with examiners estimating the probability of a match between recovered and known prints. This study presented a nationally representative sample of jury‐eligible adults with a hypothetical robbery case in which an examiner opined on the likelihood that a defendant\u27s fingerprints matched latent fingerprints in categorical or probabilistic terms. We studied model language developed by the U.S. Defense Forensic Science Center to summarize results of statistical analysis of the similarity between prints. Participant ratings of the likelihood the defendant left prints at the crime scene and committed the crime were similar when exposed to categorical and strong probabilistic match evidence. Participants reduced these likelihoods when exposed to the weaker probabilistic evidence, but did not otherwise discriminate among the prints assigned different match probabilities

Out-of-school media representations of science and technology and their relevance for engineering learning

Background: Many adolescents develop ideas about and attitudes toward engineering through their exposure to out-of-school representations of science and technology. Yet few studies have investigated the nature of these representations and found ways to use them in formal engineering learning. Purpose: This article explores media representations of science and technology that today's adolescents are familiar with. It analyzes how the embedded representations compare with those found in academic engineering and examines how these representations influence students' knowledge of and dispositions toward engineering. Design/Method: In a design-based research project, a group of high school students personally selected texts (found in magazines, videos, Web sites) related to topics of mechanics and electricity. A constant comparative method was used to analyze student interviews, while discourse analysis was used to analyze their selected texts. The analyses of two exemplary texts, a Motor Trend automobile magazine article and a Mythbusters television episode, are presented to illustrate the main findings. Results: Several characteristics of out-of-school representations are similar to engineering representations in their explanations of technically complex systems, prototype building, and testing. Out-of-school representations also present contrasting views of technology due to the diverging practices and rhetorical purposes of media professionals. This contrast poses affective challenges for beginning engineering students. Conclusions: Because out-of-school representations have the potential to shape adolescents' interests, we need to understand how they create both opportunities and obstacles for engineering education and public communication